The present invention relates to an apparatus for the measured dispensing of liquids from a storage container, particularly for the measured dispensing of beverage concentrates in an automatic beverage dispenser, where drinks can be prepared by mixing a diluent, e.g. carbonated water, and at least one beverage concentrate stored in a storage tank. More specifically, the present invention relates to an apparatus for dispensing consecutive, individual portions of concentrate from the storage container synchronously with the opening and closing of a delivery valve through which the diluent is supplied to a mixing station in the beverage dispenser.
Such an apparatus is preferably able to make available for the mixing process, in automatic beverage dispensers in which carbonated water is mixed with beverage concentrates into a soft drink, the beverage concentrates from one of the two storage containers in a volume-regulated amount and the carbonated water as the other liquid. The mix proportions attained in such automatic beverage dispensers of beverage concentrates to carbonated water in the finished soft drink should if possible be so precise that the drink prepared in the automatic beverage dispenser will if possible attain the standard of comparable pre-mix drinks on the market in bottles or cans. In order to be able to produce the precision in the mix proportions, and hence the high quality of the beverage, it is necessary to be able to dispense both the beverage concentrates and the carbonated water with corresponding high precision as far as volume is concerned.
For placement into automatic beverage dispensers to dispense beverage concentrates, dosage chamber devices have been developed. These dosage chamber devices are attached to a storage tank with the dispensing mouth at the bottom. By means of a magnet system a control valve inside this dosage chamber device is raised from a lower position, where the outlet port of the chamber is closed, to a higher position, where the inlet port of the chamber is closed, so that the contents of the dosage chamber can flow out by force of gravity. However, the dosage chamber space can become filled with air. When the control valve resumes its lower position, the beverage concentrate stored in the storage tank ends up in the dosage chamber by force of gravity, and any air in the dosage chamber will flow into the storage tank. The control force needed to activate the control valve is correspondingly slight, since no actual propulsion force need be produced. These are storage tanks with either rigid or flexible walls. In both cases there is an exchange of volume through extracting beverage concentrates by the use of air.
The above-described dosage chamber devices are very difficult to reduce in size due to technical realities relating to size and the volume they dispense. They are above all suited for dispensing concentrates for 1/10 drink portion units. For smaller amounts greater problems with functioning and dosage precision are presented. So these known dosage chamber dispensers make it difficult to dispense individual drinks on demand.
For making available carbonated water for mixing with beverage concentrates devices have been developed, water prepared and stored under high pressure in a carbonator can be dispensed in a flow-through regulated way by a flow-volume regulator and also be a volume-regulating timed valve.
It is also possible to deliver beverage concentrates from the storage container to the mixing area for mixing and preparation of beverages by using a piston pump system. Piston pump systems for this purpose require, compared to the known dosage chamber dispensers, a higher drive output, but they offer the possibility to portion out the beverage concentrates in essentially smaller individual amounts and with higher dispensing frequency, so that drinks can be mixed in individual, fixed amounts on a practically continuous basis.
The measures required to deliver beverage concentrates on one hand and carbonated water on the other for the purpose of making them into a drink have been chosen and optimized according to the particular requirements and conditions. But since these measures necessarily vary and present peculiar characteristics, care must be taken that these varying characteristics do not have any disadvantageous consequences for the intended mix proportions of the ready drink, and indeed are independent of what amount of ready drink is being mixed and prepared.
Considering these facts, the present invention provides such a device which, with the least amount of effort, will ensure that a particular mix relationship of two liquids, syrup concentrate and carbonated water, brought together at a mixing station, will remain very precise and repeatable over a long period of use independently of the particular dispensing volumes.